Decision Time, Would like some input from the forum

[Speedy3861]

So your mechanic thinks that changing the winter rating like that will help to mitigate the effects of fuel dilution?

I guess we'll find out........

 

[ZeeOSix]

I may succumb to curiosity and do a UOA anyway, but they indicated that going to 5W-20 would have no effect on warranty, but should reduce thinning by fuel dilution, ...

Fuel dilution is not a function of the oil viscosity - it's a function of the ECU tune for engine fueling & combustion and the level of the rings blowing by combustion gasses. Only way to help mitigate the reduction of the oil viscosity from fuel dilution is to: a) use a thicker hot viscosity rating and/or b) change the oil more often.

 

[Speedy3861]

Fuel dilution is not a function of the oil viscosity - it's a function of the ECU tune for engine fueling & combustion and the level of the rings blowing by combustion gasses. Only way to help mitigate the reduction of the oil viscosity from fuel dilution is to: a) use a thicker hot viscosity rating and/or b) change the oil more often.

I'm planning a UOA at 4k, to see if the EP does better than the AFE, if not better will change intervals to 4k, strangely the dilution in my 19 Civic Touring Coupe was always in the .5% or less with 5k intervals and AFE, the CRV, which is essentially the same engine with a bit more boost is tougher on oil. Perhaps more boost, more dilution. I know the tune is different because it's a heavier vehicle and, not surprisingly, uses a bit more fuel

 

[kschachn]

What analysis laboratory are you using to determine fuel dilution?

 

[Speedy3861]

Blackstone Labs

 

[kschachn]

Yeah they have had a history of not being able to accurately measure fuel dilution due to their indirect method of inference from flash point. I’d suggest you find a lab that utilizes gas chromatography to measure dilution.

 

[Speedy3861]

The dilution concerns me less than the drop out of grade in 4000 miles.

 

[kschachn]

The dilution concerns me less than the drop out of grade in 4000 miles.

Which comes first?

 

[Speedy3861]

Which comes first?

I would surmise that they're closely interrelated, what lab do you prefer?

 

[Speedy3861]

Thinning out of grade due to fuel dilution is a function of the grade. If that's what you're worried about then use a higher grade oil.

That's what I discussed today with my dealer's service manager, and my Technician, both agreed that there's absolutely nothing to lose by switching to Mobil1 0W-30 AFE. Honda apparently has no further mystical fixes for the 1.5t, so unless I want to do 2.5k OCI's, the 0W-30 will be a better choice. Endless trials of 0W-20 won't find a magical formulation that will stay in grade for 5k, it's just the nature of the beast.